Fuse holder



March 30, 1954 ALDEN 2,673,910

FUSE HOLDER Filed April 11, 1952 Patented Mar. 30. 1954 UNITED STATES PATENT OFFICE FUSE HOLDER Milton Alden, Wellesley, Mass.

Application April 11, 1952, Serial No. 281,780

8 Claims. 1

This invention relates to fuse holders and more particularly to holders of fuses of the cartridge type.

Objects of this invention are to provide a holder for a cartridge fuse which securely and safely restrains the fuse, which gives a positive indication when the fuse has blown or is defective, which permits the ready replacement of a defective fuse, which is economical to manufacture, which is small in size, which is simple to mount and connect, and which advances the art generally.

Accordingly the invention contemplates a holder of a nonconducting material such as a suitable molding plastic having a recess which forms a socket for receiving a cartridge fuse. Electrical contacts for connecting the fuse in an external load circuit, which are preferably molded into the body, are provided at either end of the socket. The lower contact, which is located at the bottom of the recess is preferably in the form of a cup for receiving one end of the fuse. The other contact is preferably a sleeve located adjacent the open end of the recess Where it comes into contact with a closure for the recess which restrains the fuse therein, the electrical circuit between the other end of the fuse and the sleeve contact being made through said closure. The closure also includes a lamp, one terminal of which is connected to the sleeve contact and corresponding end of the fuse by the contact of the closure with the sleeve and fuse. The other lamp terminal is connected to the body contact at the bottom of the recess by circuit means preferably including a conducting ring located in the socket adjacent the sleeve contact so that the ring abuts a similar ring in the closure, which connects with the lamp terminal. If necessary such circuit means includes a resistor for limiting the voltage drop through the lamp.

These and other objects and aspects be apparent from the following description of a specific embodiment of the invention which refers to a drawing wherein: V

Fig. 1 is a plan view of a fuse holder;

Fig. 2 is a side elevation view;

Fig. 3 is a bottom view; 7

Fig. 4 is a sectional view on line 4-4 of Fig. 1;

Fig. 5 is a sectional view of the closure; and

Fig. 6 is an isometric view of the upper contact.

As is best shown in Fig. 4, the fuse holder" consists of a hollow cylindrical body l0, which is preferably molded from an electrically nonconducting material such as a suitable plastic.

2 Molded integrally with the body Ill near the upper end thereof isa flange I2 over which is disposed an elongated mounting plate l4 having a turned down lip [6 for imparting stiffness thereto. Two opposed portions of the lip iii are swaged under the flange l2 as at [8 (Fig. 3) to secure the mounting plate M to the body Ill. At either end of the mounting plate It is provided a respective aperture for a mounting screw (not shown) each of which engages a correlated nut 22 (Fig. I). The integral flange I2 is notched at either end to receive the nuts 22 so that the nuts do not revolve as the mounting screws are tightened.

The lower end of the body I0 is closed by an integrally molded head 24 (Fig. 4) so that the resulting recess forms a socket to receive a cartridge fuse F as will be described in detail hereinafter. Secured to the'head 24 by a rivet 26 is a lower electrical contact such as the flexible cup 28 formed of sheet metal so as to receive the lower end of the fuse F with a snug fit. The bottom surface of the head 24 is recessed to receive a lug 36 which is secured under the head of the rivet 26. The outwardly projecting end of the lug 30 is apertured and bent downwardly to facilitate the soldering thereto of an electrical conductor (not shown) of an external load circuit which forms no part of th present invention.

The other conductor of the load circuit is soldered to a lug 32 formed integrally with a split sleeve 34 (such as is shown in Fig. 6) of sheet metal which is located in the body 10 a short distance below the open end thereof so that the soldering lug projects outwardly through a slotted aperture in the side wall of the body thus forming an upper contact. After the lug 32 has been inserted through the slotted aperture the parallel edges thereof are bent down to lock the sleeve 34 in position.

It is to be noted that the split sleeve 34 does not come directly into engagement with the upper end of the fuse F but that the electrical connection therebetween is made through a closure 35 which also serves to secure the fuse in the socket. To this end the split sleeve 34 is provided with internal threads which engage corresponding external threads upon a hollow sleeve 35 of an electrically conducting material forming a part of the closure 35. The lower end of the sleeve 36 is bent inwardly and formed into a nipple such as the hollow rivet 38 for securing a cup 40 formedof sheet metal. The cup 40 is split and has a slightly smaller diameter than the end of the fuse F so that the cup is deformed as the end of the fuse is forced therein. The above arrangement makes it possible to put the end of the fuse F in the cup 40 with the closure 35 separated from the body and then insert the closure and fuse as a unit in the socket. The closure 35 is then rotated to engage the threads of the split sleeve 34 whereby the lower end of the fuse is forced into the lower cup 28 against the force exerted by a spring 42 located therein.

It will be evident that the above described arrangement connects the fuse F in a load circuit soldered to the lugs 33 and 32 by an electrical path including the lug 30, the rivet 2B, the lower cup 28, the fuse F, the closure cup 43, the closure sleeve 36 and the split sleeve 34 to the upper lug 32. If however this circuit is interrupted by the blowing of the fuse F circuit means are provided for energizing a signalling device such as a neon lamp L (Fig. which is incorporated in the closring it is positioned immediately above the hollow sleeve 36 of the closure so that the rings are in electrical contact when the closure threadingly engages the body recess as is shown in F t. The lead forming one of the terminals for the lamp L is soldered to the ring 43 as at 33, the other terminal lead 52 being soldered to the rivet 3B.

The hollow sleeve 36, the lamp L and the ring are maintained in their relative positions and electrically insulated from one another by means of a suitable nonconducting plastic material which is preferably molded thereabout. Although it is possible to use an opaque material with an open window therein or permit the lamp L to pro- J'ect beyond the surface thereof, I prefer to use a transparent or translucent material which completely surrounds the lamp to form a diffuser 55 for the light rays therefrom. This diffusing action is aided by the flats 58 on the side of the diffuser and the sector serrations 58 on the top thereof, the flats also servin to provide a grip which aids in removing the closure 35 from the body recess.

It will be evident that the above described configuration provides circuit means including the bottom lug iii], the resistor R, the rings 45 and t8, the lamp L, the hollow sleeve 36, the split sleeve 3 and the upper lug. 32 which circuit means is in parallel with the fuse F so that if the fuse is blown, the open circuit voltage of the load circuit is applied across the series combination of the lamp and resistor thereby to light the lamp as the indi cation of a blown fuse. It will also be evident that on low voltage circuits or by which a high voltage lamp is used the resistor R can be replaced by a jumper or shunt which directly electrically links the bottom lug 3llwith ring Q6.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and body having a recess therein for receiving the fuse,

The other resistor lead is sol- 1 and a closure for the recess; said closure comprising an insulating member, a lamp in said member visible through one end thereof, a connector at the opposite end of said member connected to one lamp terminal, a fuse-holding contact attached to said connector so as to extend beyond said member, contact means on said member intermediate the ends thereof and insulated from said connector by said member; said body comprising a terminal mechanically and electrically engaging said connector, a fuse contact in said recess, contact means on the body adjacent the outer end of said recess adapted to connect with the closure contact means when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and contact means for connecting the lamp in parallel with said fuse contacts.

2. A holder for a cartridge fuse comprising a body having a recess therein for receiving the fuse, and a closure for the recess; said closure comprising an insulatin member, a lamp in said member visible through one end thereof, a connector at the opposite end of said member connected to one lamp terminal, a fuse-holding contact attached to said connector so as to extend beyond said member, contact means on said member intermediate the ends thereof and insulated from said connector by said member; said body comprising a terminal mechanically and electrically engaging said connector, a fuse contact in said recess, contact means on the body adjacent the outer end of said recess adapted to connect with the closure contact means when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and contact means for connecting the lamp in parallel with said fuse contacts, said 1 mp, connector, fuse-holding contactand contact means being molded as an integral unit in said closure member.

3. A holder for a cartridge fuse comprising a body having a recess therein for receiving the fuse, and a closure for the recess; said closure compris ing an insulating member, a lamp in said member visible through one ,end thereof, a, connector at the opposite end of said member connected to one lamp terminal, a fuse-holding contact attached to said connector so as to extend beyond said member, contact means on said member intermediate the ends thereof and insulated from said connector by said member; said body comprising a terminal mechanically and electrically engaging said connector, a fuse contact in said recess, contact means on the body adjacent the outer end of said recess adapted to connectwith the closure contact means when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and con tact means for connecting the lamp in parallel with said fuse contacts, said lamp, connector, fuse-holding contact and contact means being molded as an integral unit in said closure member, and said closure member comprising translucent material molded to form an integral diffusing lens forsaidlamp.

4. The fuse holder according to claim 13 characterized in that said closure is formed of a translucent plastic and said lens comprises sector serrations at the lamp end of said closure.

5. A holder for a cartridge fuse comprising a body having a recess therein for receiving the fuse; and a closure for the recess said closure comprising an insulating member, a lamp in said member visible through one end thereof, a connector at the opposite end of said member connected to one lamp terminal, a fuse-holding contact attached to said connector so as to extend. beyond said member, contact means on said member intermediate the ends thereof and insulated from said connector by said member; said body comprising a terminal mechanically and electrically engaging said connector, a fuse contact in said recess, contact means on the body adjacent the outer end of said recess adapted to connect with the closure contact means when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and contact means for connecting the lamp in parallel with said fuse contacts, said lamp, connector, fuse-holding contact and contact means being molded as an integral unit in said closure member and said lamp extending substantially the length of said member, one end of the lamp extending inside said connector.

6. A holder for a cartridge fuse comprising a. body having a recess therein for receiving the fuse, and a closure for the recess; said closure comprising a cylindrical insulating member,

having a portion of reduced diameter forming a shoulder abutting the body at the end of said recess, a lamp in said member visible through one end thereof, a connector at the opposite end of said reduced portion connected to one lamp terminal, a fuse-holding clip contact attached to said connector so as to extend beyond said mem her, an annular contact molded on the periphery of said shoulder intermediatethe ends thereof and spaced and insulated from said connector by said shoulder; said body comprising a terminal and electrically engaging said connector, a fuse contact at the inner end of said recess, contact means on the body adjacent the outer end of said recess adapted to connect with said annular contact when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and body contact means for connecting the lamp in parallel with said fuse contacts.

7. A holder according to claim 1 characterized in that said contact means comprise mating rings molded in said body and closure respectively.

8. A holder for a cartridge fuse comprising a body having a recess therein for receiving the fuse, and a closure for the recess; said closure comprising a cylindrical insulating member, a lamp in said member and visible through one end thereof, a threaded annular connector molded on the opposite end of said member and connected to one lamp terminal, a fuse-holding clip contact attached to said connector so as to extend beyond said member, contact means on the periphery of said member intermediate the ends thereof and spaced and insulated from said connector by said member; said body comprising a threaded terminal sleeve mechanically and electrically engaging said connector, a fuse contact at the inner end of said recess, contact means on the body adjacent the outer end of said recess adapted to connect with the closure contact means when said closure is engaged in said body, and circuit means in said recess connected between said body fuse contact and body contact means for connecting the lamp in parallel with said fuse contacts.

MILTON ALDEN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,386,060 Powell Oct. 2, 19%5 2,448,389 Powell Aug. 31, 1943 

